Our holdings include hundreds of glass and film negatives/transparencies that we've scanned ourselves; in addition, many other photos on this site were extracted from reference images (high-resolution tiffs) in the Library of Congress research archive. (To query the database click here.) They are adjusted, restored and reworked by your webmaster in accordance with his aesthetic sensibilities before being downsized and turned into the jpegs you see here. All of these images (including "derivative works") are protected by copyright laws of the United States and other jurisdictions and may not be sold, reproduced or otherwise used for commercial purposes without permission.
Vintage photos of:
October 1942. State School of Mines in Golden, Colorado. "Speed in metallurgical analysis, to match the rapidity with which the nation arms itself, is possible through use of the spectrograph, a marvelous new machine used for study of materials through measurements of the arc of light they emit when heated. The aluminum and magnesium industries, steel companies and foundries use it for quick study of metals. Mines use it for exploration. The spectrograph will yield an analysis of seven elements in 15 minutes, which would require up to four hours by old chemical methods. Students in defense training courses at a famous mining-engineering school listen as an instructor shows them how the machine operates." Photo by Andreas Feininger, Office of War Information. View full size.